1. Field of Invention
The forward motion of a motor boat in water causes the displacement and subsequent turbulence in the water which is cumulative and greatest just behind the boat. A spinning propeller of an outboard motor in these turbulent water conditions turns, at least in part, in the direction of the turbulent water results in a lessening of forward thrust of the boat. A propeller in undisturbed water can make contact with the water so that the action of the propeller with the water acts to maximally accelerate the boat. The present invention helps the boat operator to position the outboard motor away from the turbulent water to aid in acceleration.
2. Description of Prior Art
To avoid placement of the propeller in the turbulence created by the moving boat, boat operators can position the outboard so as to place the propeller of the outboard in a location where turbulence is at a minimum. Calmer water will be found below and aft of the boat. Traditionally jack plates that attach the outboard motor to the boat have one bracket attached to the boat's transom and the other bracket attached to the outboard motor. The sliding of one bracket against the other bracket is commonly a feature in the devices and provides the movement to raise or lower the outboard motor.
Sliding can be achieved by telescoping tubular elements which are aligned in the longitudinal axes of each of the brackets. The tubes having the greater diameter house the tubular elements of the other bracket and the smaller diameter elements slide within the larger diameter elements to raise or lower the attached motor.
Another means for sliding utilizes side mounted bolts on the transom bracket which fit into and slide within side slots on the outboard bracket. The operator positions the motor, and to maintain the vertical position of the outboard the bolts are tightened. In another jack plate, the side edges of the transom bracket fit into grooves on the outboard bracket. Lubricated bearings aid in the sliding motion. Similarly, in another invention, sliding of the motor mounted bracket against the transom bracket is accomplished by the motor bracket having both tubular and channel fittings that complementarily fit the channel and tubular fittings on the receiving bracket. The fittings are mounted on the side edges of the brackets.
Rather than use a means for sliding of the brackets, the outboard motor can be mechanically lifted as in a separate application. The movement of the transom bracket relative to the motor bracket is accomplished by the brackets being pivotally attached with upper and lower links in the form of steel plates, this design is referred to as the parallelogram design. The upper link is attached to the upper edges of both of the brackets and the lower link is similarly attached to the lower edges. A hydraulic cylinder is mounted between the pivotal links of the motor bracket and the transom bracket so that the lengthening or shortening of the cylinder will raise or lower the motor, respectively.
Hydraulic systems are a conventional part of many of these inventions. The systems include a cylinder attached to both brackets so as to move the transom portion and the outboard portion distant to raise the motor or to move them together to lower the motor. An electrically powered reversible hydraulic pump is used to control the amount of hydraulic fluid in the cylinder. Once the operator has the outboard motor in the desired position the cylinder holds the motor in place.
A jack plate using a ratchet and pawl system to provide the power slides the transom brackets relative to the motor brackets. A nut when turned by a wrench rotates a shaft connected to the transom bracket. A cable connects the shaft to the motor bracket. Rotation of the shaft winds or unwinds the cable around the shaft to raise or lower the motor bracket and motor.
Available devices while primarily attaching the outboard to the boat, secondarily combine components to raise and lower the outboard, supply power for that movement and enable the operator to lock the outboard in position. But outboard motors are routinely exposed to harsh environments with little upkeep. The heaviness of the motor, the maneuvering of the boat and the transport of the motorized boat call for a jack plate that is resilient and stable. Mechanized systems, systems that require lubrication or systems that involve many pieces may not be suited to the conditions in which the motor functions. A need exists for a jack plate that while it attaches the motor to the boat and allows the operator to position the motor into water that optimally increases forward thrust, can weather the conditions of the outdoors in a dependable and stable fashion.